// @flow
// Copyright (c) 2018 Uber Technologies, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
// in compliance with the License. You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software distributed under the License
// is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
// or implied. See the License for the specific language governing permissions and limitations under
// the License.

/**
 * Throttler is used to rate limits operations. For example, given how debug spans
 * are always sampled, a throttler can be enabled per client to rate limit the amount
 * of debug spans a client can start.
 */
declare interface Throttler {
  isAllowed(operation: string): boolean;
  close(callback?: Function): void;
}

declare type CreditResponse = {
  operation: string,
  balance: number,
};
